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Wing endplates / side dams

What do endplates on a car wing do? · Standard part · basis: Design rules and figures from the cited sources; example geometry by Xem Studio

Also called: wing endplates, end plates, side dams, wing side plates, endplate size, rc wing side dams, wing tip vortex plate, endplate design, car wing end plate, spoiler side plates

Exact dimensions. True size, with no printing tolerance added.

sizes
6 in table

Notes

  • Endplates limit air spilling around the wing tips from the high-pressure side to the low-pressure side, which raises downforce and efficiency (HPA).
  • UIUC tests found a larger endplate raised CL by about 0.096 at constant angle and cut drag 13.7% at constant CL (Jasinski & Selig).
  • HPA's ballpark for home-built plates is to extend twice as far below the wing as above it. RC classes cap side-dam size in their rules, e.g. 40 x 20 mm on 1/10 touring cars (AARCMCC) and 80 x 80 mm on 1/10 off-road buggies (EFRA).
  • Used on: Champ Car endplate (UIUC test).
  • The file is a reference example built by Xem Studio from the numbers above (1/10 touring-car limits: 190 mm width, 40 mm chord, 20 mm side dam.). Sizes the sources do not fix are illustrative; scale the example to your own vehicle.

Wing endplates / side dams size chart

parametervalue or rangesource
Endplate proportion (rule of thumb)2x as far below as above, e.g. 100 mm above, 200 mm belowHPA rear wing
Larger endplate effect+0.0958 CL at constant alpha; -13.7% CD at constant CLJasinski & Selig (UIUC)
1/10 touring car side dammax 40 mm wide x 20 mm highAARCMCC
1/10 track car endplates25 mm above body x 100 mm deepAARCMCC
1/10 off-road side dammust fit an 80 x 80 mm rectangleEFRA
1/12 pan car side dammax 72 mm highEFRA

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

High Performance AcademyAerodynamic performance devices for club level cars: rear wing theorywebPublisher's page; dimensions are facts
University of Illinois / SAEExperimental Study of Open-Wheel Race-Car Front Wings (Jasinski & Selig, SAE 1998)webPublisher's page; dimensions are facts
AARCMCCSection 3: Electric On Road, Technical Rules (Oct 2006)webPublisher's page; dimensions are facts
EFRAEFRA Handbook 2010, Appendix 3: Electric CarswebPublisher's page; dimensions are facts

Free files

★ Free files 1 parts. Xem Studio design: free to use, print and sell things from; not to be republished as files. Xem Studio Design License. index.json

wing-endplates-rear-wingsingle rear wing: span 190 × chord 40 mm at 6°, endplates 20 mm, inverted NACA 4412 section (mounts from below)STEP · STL
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Plain text: sheet.txt · JSON: /api/geometry?object=wing-endplates

Wing endplates / side dams, isometric render of a generated part
Render of wing-endplates-rear-wing from the free STEP; not to scale.

Fits with

Single-element rear wing (race car), isometric render of a generated part
Single-element rear wing (race car)7 sizes★ 1 file
Dual-element (two-element) rear wing, isometric render of a generated part
Dual-element (two-element) rear wing9 sizes★ 1 file
Swan-neck rear wing mount, isometric render of a generated part
Swan-neck rear wing mount5 sizes★ 1 file
Gurney flap / wickerbill, isometric render of a generated part
Gurney flap / wickerbill7 sizes★ 1 file
Front splitter, isometric render of a generated part
Front splitter8 sizes★ 1 file
Splitter tunnels (front diffuser), isometric render of a generated part
Splitter tunnels (front diffuser)5 sizes★ 1 file

Questions

Do endplates add drag?

In the UIUC test a larger endplate actually reduced drag at constant lift by 13.7% (Jasinski & Selig).